1. Field of the Invention
The present invention relates generally to a control lever assembly for operating a control system of a vehicle. More specifically, the present invention relates to an improved control lever assembly including a control lever rotatably supported by a control lever support.
2. Description of the Related Art
Motorcycle control levers are commonly mounted to the motorcycle's handlebar to permit a rider to operate a control system of the motorcycle, such as a manual clutch system or a front brake system. Typically, the control lever is rotatably supported by a lever support, or perch, which is clamped to the handlebar at a position inward of a handgrip. The control lever rotates about a pivot axis to impart a pulling force on a bowden wire arrangement (or impart a pushing force on a hydraulic piston, if the control system is hydraulically actuated) and thereby operate the control system. Thus, rotational motion of the control lever is converted into linear movement of the bowden wire (or piston).
With reference to FIG. 1, an example of a prior art control lever mount arrangement is illustrated. The prior art mount arrangement includes a control lever support, or perch 1, which is configured to be connected to a handlebar of an associated vehicle (not shown). The perch 1, includes a pair of spaced apart flanges 2 that extend generally in a radial direction from the handlebar. A mount portion of a control lever 3 is received between the flanges 2. A pivot bolt 4 passes through aligned bores 5 of the flanges 2 and through an aperture 6 of the control lever 3. A nut 7 secures the pivot bolt 4 to the perch 1. In some arrangements, a bushing 8 may be positioned between the control lever 3 and the pivot bolt 4. Typically, the bushing 8 is fixed with respect to the control lever 3 and, thus, rotates with respect to the pivot bolt 4.
Thus, the control lever 3 is rotatable about a pivot axis PA defined by the pivot bolt 4. One problem with such an arrangement is that a space, or gap, often exists between the aperture 6 of the control lever 3 and an external surface of an adjacent portion of the pivot bolt 4. This gap may exist due to normal manufacturing variations or may be a result of other factors, such as the pivot bolt 4 and control lever 3 originating from different manufacturers. Similarly, a gap may exist between upper and lower surfaces of the control lever 3 and the flanges 2. Gaps in these two areas may permit significant undesired movement of the control lever 3, that is, movement in directions other than rotation about the pivot axis PA.
Although the actual gap may be relatively small, the undesired movement is magnified at points along the control lever 3 away from the pivot axis PA. Accordingly, at the finger grip portion of the control lever 3 (i.e., the portion grasped by the rider), the amount of undesired movement is often significant. This undesired movement, or play, may be a source of annoyance to a rider of the motorcycle and especially to motorcycle racers, who rely on the ability to precisely operate the various lever-actuated control systems of the motorcycle.
Another problem with the control lever mount arrangement of the type illustrated in FIG. 1 is that the performance of the lever may be affected by a pivot bolt 4 and/or nut 7 that is overly tightened. Over-tightening of the pivot bolt 4 and/or nut 7 may collapse the flanges 2 toward one another thereby causing contact between the inner surfaces of the flanges 2 and the adjacent, outer surfaces of the control lever 3. Under-tightening of the nut 7, however, may result in the nut 7 loosening due to vibrations transmitted to the control lever perch 1 by the engine of the vehicle.